This invention relates to hypochlorite compositions and, more particularly, to such compositions containing an inorganic pigment system comprising at least cobalt aluminate as a coloring agent.
Hypochlorite compositions are widely used in the home and in industry that take advantage of the oxidizing capability of the hypochlorite. Thus, they have been used as textile bleaching agents and in the general purpose cleaning and bleaching of hard surfaces such as dishes, glasses, metal surfaces, pots, pans, sinks, tubs, toilet bowls and the like. It is also used in scouring abrasive compositions. Because of its capability of attacking protein fibers and food, it has been used in compositions designed as drain cleaners, i.e., for unclogging clogged drains.
In certain of these applications it is advantageous to color the hypochlorite compositions. A blue color is often preferred. However, because of the propensity of the hypochlorite to destroy most organic coloring agents, this has presented something of a problem.
Efforts have been made to avoid this problem by using inorganic pigments as coloring agents. The pigment most widely used to provide a color to hypochlorite compositions has been ultramarine, especially ultramarine blue. Ultramarines are a class of pigments that are essentially blue but have shades ranging from a red cast (called ultramarine violet or ultramarine red) to a green cast (called ultramarine green). These have been described as complex combinations of silica, alumina, soda and chemically combined sulfur. Ultramarine blue has most typically been incorporated in the prior art compositions, blue being the color consumers seem to prefer in cleaning compositions such as herein described.
However, the use of ultramarines in hypochlorite containing compositions has left something to be desired. More particularly, the capability of these compositions to retain their color at a satisfactory level under storage conditions over extended periods of time has been found to be wanting.